-As you stretch into the day's first downward-facing dog pose, consider that despite having been around thousands of years, scientifically rigorous studies of yoga's effectiveness are scant.

So folks at the National Center for Complementary and Alternative Medicine, part of the National Institutes of Health, decided consumers could benefit from knowing about a few of the most recent studies on yoga's effectiveness in easing such common conditions as low-back pain, asthma and arthritis. They produced a new video -- free online -- featuring researchers George Salem of University of Southern California and Karen Sherman of Group Health Research Institute in Seattle.
In one study, Salem and colleagues aimed quantify the biomechanics, forces, muscle recruitment patterns and torque in healthy older people as they moved through yoga poses by wiring them to high-tech tools.
Preliminary results, Salem says in the video, were surprisingly counterintuitive.
Poses researchers thought targeted certain muscle groups actually targeted others. Poses they believed were safe appeared less so under laboratory scrutiny.
For instance, warrior poses thought important for increasing balance by targeting the outer thigh muscles actually targeted the muscles of the inner thigh. Researchers found tree poses much better for building balance.
Salem says such information should help yoga instructors better design programs appropriate for older people concerned with balance.
In Seattle, Sherman hoped to discover whether yoga could alleviate something for which there's often believed to be no cure: low-back pain.
"I was actually surprised that yoga did work," Sherman says in the video. It was clearly superior to typical prescriptions for care and better than typically prescribed exercises, "not enormously better," she says, "but statistically significant and intriguing."
The takeaway: A carefully adapted set of yoga poses, individualized for each patient, can reduce pain and improve function.
Yoga, on the other hand, hasn't been found helpful for treating asthma, according to the National Center for Complementary and Alternative Medicine, and studies looking at yoga to alleviate arthritis symptoms have had mixed results.
- Katy Muldoon; twitter.com/katymuldoon
(c)2012 The Oregonian (Portland, Ore.)
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